Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations only declare destructiveHint=true, so the description carries most of the burden: it explains the failure semantics (check goes down when no ping arrives within period), discloses the returned identifier (data.new_id), and routes to the tool that exposes the ping URL. It does not cover auth/permission requirements or what happens to pings before the check is live.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Two compact sentences plus the endpoint note, all front-loaded: purpose, failure condition, return value, and follow-up tool. No filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully documents the return field (data.new_id) and the next step to get the ping URL, which is essential for actually using a heartbeat check. Remaining gaps (auth needs, initial ping state) are minor for a straightforward create call.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100%, so every parameter is already documented (period range, empty-list clearing for tags/contact_groups). The description reinforces the meaning of `period` in the failure lifecycle but adds no syntax or format detail beyond the schema, so baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Create a heartbeat (push) check') and immediately scopes it to cron jobs/workers, which cleanly separates it from the sibling create tools for uptime/SSL checks. The mechanism (down if StatusCake is not pinged within `period` seconds) makes the resource unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explains the use case (monitoring a cron job or worker) and prescribes the follow-up step: fetch with statuscake_get_heartbeat_check to obtain the ping URL. It does not explicitly say when to prefer this over statuscake_create_uptime_check, but the cron/push framing implies the boundary well.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.